1. Field Of The Invention
This invention relates to electronic image recording/playback apparatus and, more particularly, to the selection of a predetermined operating mode when an electronic still camera is connected to an electronic player.
2. Description Of The Prior Art
So-called electronic still cameras have been introduced in which video signals are generated in response to a sensed image and recorded on a magnetic medium, such as a miniaturized floppy disk. Video picture signals, produced when the recorded video signals are played back, may be displayed on a monitor, such as a conventional television receiver, or may be "printed" to form a "hard copy" image corresponding thereto.
Although separate stand-alone players are known for playing back previously recorded video signals from a floppy disk, it is advantageous to use the operating components of the electronic still camera to reproduce those video signals. Often, the reproduced video signals are not in a format compatible with most conventional monitors or television receivers. For example, the reproduced video signals may not be in the NTSC format. Accordingly, further signal processing of the reproduced video signals often is desired; and an electronic player typically is electrically connected to the electronic camera so as to process the reproduced video signals and, thus, produce picture signals which may be displayed on a monitor or television receiver. The electronic player normally is provided with an output terminal adapted to be connected to the input of such a monitor or television display. When a user actuates a playback button, or switch, disposed on the electronic player, a playback operation is carried out, whereupon the video signals are reproduced from the magnetic medium, processed and supplied to the monitor/display.
A typical electronic player is a separate device normally not connected to the electronic camera unless and until a playback operation is desired. To facilitate portability and use "in-the-field", the player is provided with a battery which functions as its power source. The battery may be of the rechargeable type or, alternatively, a non-rechargeable "primary battery" may be used.
The power source for the camera likewise is a battery; and it too may be a rechargeable battery or a primary battery. When a rechargeable battery is used as the camera power source, a charging unit generally dedicated for use only with the camera must be provided; and the camera normally cannot be used in an operating mode (e.g. recording or playback) while its battery is being charged.
As mentioned above, the electronic player normally is not coupled to the camera unless and until an image playback operation is desired. However, a playback operation typically is not initiated until the user actuates the playback button, even though the camera, player and monitor may be properly connected. In some systems, the playback button is concealed to avoid inadvertent operation of the player. In other systems, the playback button may be included in an array of operating controls, and the user may erroneously actuate the wrong control. It is desirable to simplify a playback operation.
Although the camera and player both may be provided with batteries as their respective power sources, these batteries generally are used independently of each other even when the camera and player are connected. For a playback operation, the camera is powered by the camera battery and the player is powered by the player battery. Thus, power is drawn from both batteries and both are subject to rapid depletion. If a rather lengthy playback operation is carried out, or if several brief playback operations are performed, the camera battery voltage may be significantly reduced. Consequently, the camera battery may need to be recharged before a signal recording operation next can be achieved. This means that the user of the electronic camera may miss a desirable photographic opportunity.
In many conventional electronic cameras using rechargeable batteries as a power source, battery recharging requires removal of the battery from the camera and loading of same into a charging unit. Often, battery removal and loading is complicated. Further complications arise when both the camera and player batteries are to be recharged. Moreover, even the relatively simple task of removing and loading one or both batteries is time consuming.